Naruto: The Hidden Sannin
by Darkcloudalpha
Summary: After hearing a desperate please from Iruka, the Hokage enlists the help of a unlikely ninja to help train Naruto in the foundations of being a ninja. Who does he chose? Kosuke Maruboshi the Eternal Genin, a ninja once trained by the Second and Third Hokage, can he help Naruto with his dream of becoming the ninja he dreams of being?


_**Disclaimer: I don't own Naruto**_

 _ **Author Comments: First chapter in a story I was rolling around in my head. For those of you following Naruto: The Gamer I have not given up on the story and I am now in the process of reviewing it. I may need to do a bit of rewriting on parts of it, but in the meantime I needed to get my writing muscles working so I thought I would work a bit on this.**_

 **Naruto: The Hidden Sannin**

Iruka Umino rubbed his temples and tried to keep a headache from coming. It had been a long day trying to maintain order in his class and he still had mounds of paperwork before his duties would be done, but Iruka had another problem that was bothering him more and more as of late.

That problem was Naruto Uzumaki.

It had been several months since the Third Hokage had spoken with him and opened Iruka's eyes to the plight of his most rebellious student and Iruka was still accepting the change in how he viewed the young boy. He no longer thought of the him as a monster, and truth be told, he was starting to see a lot of himself in Naruto and wanted to do the best he could to help the boy becomes the best ninja he could be, just as he dreamed and bragged about. In the past, whenever Naruto would brag about being the best ninja in the village or becoming Hokage, Iruka would just silence him or, more often, ignore him altogether. Now Iruka genuinely wanted to help him achieve his dreams.

The issue was he was failing.

Naruto was dead last in his class, he could not focus on his lessons and spent most of his time acting up in class as opposed to working harder. Iruka now understood the reasons for this, but could not for the life of him think of a way to help more than he already was. As a teacher, he was supposed to treat every student equally but he had started to spend what precious little extra time he had trying to get Naruto into shape, but it was not enough.

For the young teacher, it was a matter of time and help, he had dozens of students he had to prepare for the life of a shinobi, and even if many of them would not be able to pass the harsh requirements of ninja life, he could not take too much time from their education to help one student. Iruka had pleaded with other teachers to help him by focusing more of their time on the young ninja, but his pleas were ignored, not that he was surprised, most teachers either hated Naruto or distrusted the Fox within him and refused to help Naruto in any way. As a result Naruto was falling further behind, which had lead Iruka to this final act of desperation.

Iruka was waiting outside the Hokage's office, he was here to petition Lord Sarutobi for help, normally of course the Hokage wouldn't take special interest in a student, a failing one at that, but both the young teacher and the Hokage knew that Naruto was a special case, and not just because he held the spirit of the Nine-Tails in him.

The Hokage's secretary nodded to him and the doors to the Lord Third's office opened.

"He can you see you now Iruka." she said with a pleasant tone.

"Ah, thanks." he said back heading toward the doors. She smiled and gestured him to move on, the Hokage's time was precious and it would be best to not waste it, her eyes seemed to say. Iruka started into his office, he had spent more time with the Hokage than most chūnin could have, but he still felt intimidated whenever he was in the presence the legendary Professor.

"Come in Iruka." the warm voice stated, "I suppose this has something to do with Naruto?"

"Yes Lord Hokage. I have been concerned with..." Iruka paused as a unexpected presence was in the room. There sitting next to the Hokage was one of his most famous students, one of the legendary Sannin, Jiraiya the Toad Sage.

"Ah, well if you're busy Lord Third I can come back at a later time." he said nervously. He was prepared for the Hokage, but one of the Sannin as well! They had to have more important matters to discuss than any one student, no matter how important.

"Nonsense Iruka, I invited you in after all."

"Well it does concern Naruto Hokage-sama." he began nervously.

"What about Naruto?" Jiraiya interrupted gruffly. He sounded angry. Iruka gulped a bit and glanced at the Hokage.

"You can talk about anything that concerns Naruto in front of Jiraiya Iruka. He is aware of more than you when it comes to his some aspects of his situation."

"Yes Lord Hokage." shaking off his nervousness he proceeded. "It's concerns how Naruto is doing in class."

"Still poorly I take it." Sarutobi said with a sigh.

"Yes my Lord. He is doing poorly in all aspects of his training and studies. I fear if the trend continues he will not only remain dead last but will eventually be dropped altogether."

"Then why haven't you been doing anything about that?" Jiraiya asked suddenly taking a step toward the younger chūnin.

"Lord Jiraiya I have been trying to help Naruto but-"

"But! Your his teacher! It's your job to help him!"

"Enough!" Sarutobi didn't shout, but the stern tone in his voice and the killing intent in the air got the Sannin's attention and petrified Iruka.

Jiraiya turned towards the old man.

"Sensei..."

"Do not place your own guilt on him Jiraiya. He has done above and beyond to meet his duties."

Iruka was shocked as Jiraiya seemed to sink back in on himself and sat back down, but still took a moment to glower at the chūnin, Sarutobi gestured for Iruka to continue.

"Well as I was saying, I have been trying to give Naruto all the extra time I can but I can't give him enough to balance out the negative impact of those around him."

"Is anyone sabotaging him?" the Hokage asked.

Iruka shook his head. "Not that I have seen Lord Hokage, but they don't need to, learning the fundamentals of being a shinobi requires a strong backing for most children, all others need to do is ignore him and that alone might do enough to damage his skills to the point where he may be flunked out."

The Hokage nodded. "So what would you suggest Iruka?"

Iruka sighed. "Naruto is not a good self starter. He will continue to fall behind if the situation stays as it is now, however, if we could arrange for a specialized tutor to give Naruto some extra time I think he could really turn around."

"I see." the Hokage responded. "That is a good suggestion Iruka but such a arrangement is harder than you think."

"If it a matter of funds Lord Hokage I would be more than willing to to donate part of my salary towards a reliable tutor."

Sarutobi smiled. He knew that the young teacher would turn around of someone show him the value in the student he only thought he hated.

"It's not about funding Iruka, it's-"

"It's politics." Jiraiya nearly spit out.

"Politics?" Iruka asked confused.

"If the clans and civilians were not fighting each other we could have dealt with this long ago!"

"Jiraiya please, calm yourself, we need to find solutions, not rehash old arguments. " said Sarutobi.

"You're right Sensei."

The Hokage focused back on Iruka. "You see Iruka, I would love to hire a tutor for young Naruto but the sames reasons for why he is not adopted would make it difficult to find a tutor we could hire."

"I don't understand Lord Hokage, I just thought Naruto wasn't adopted because of the fear the village had for him?"

"Politics," Jiraiya said again, thought this time far more calmly, "Naruto may be feared right now, but that is the same in every village with a Jinchuuriki. What's different for Naruto is the circumstances of his birth."

"His birth?" Iruka asked. The Sannin looked at the Hokage who gave his permission with a slight nod.

"Naruto is the son of the Minato Namikaze and Kushina Uzumaki."

Iruka's eyes widened. "The son of the Fourth!"

Jiraiya nodded. "Naruto's secret status as the Nine-Tails is mostly only secret to the younger generations in our own village. Due to the civilian knowledge of the secret most other villages are aware of his status as a Jinchuuriki, though several of them think he just a plant to protect the real Jinchuuriki, since there is no way we would ever let a Jinchuuriki walk around so lightly guarded." The Sannin grinned with that one, he had spread that bit of misinformation for years.

"A Jinchuuriki is a known factor in village politics and unless a rather good opportunity presents itself most villages would not risk a war going after Naruto just for being a possible Jinchuuriki. The son of the Fourth and one of the last Uzumaki however..."

Iruka considered the possibilities, many desired the bloodline of the Uzumaki Clan and many wanted revenge on the Yellow Flash, Iwagakure would definitely risk a war for a chance to capture or kill the son of a hated foe.

"Okay I get the need for the secret but what does that have to do with Naruto being adopted?"

"Naruto may be a child now but someday he will be a adult, a very powerful adult with access to all the political clout of being a Jinchuuriki, son of one of the most powerful shinobi born, and heir to the Uzumaki Clan. Many of the clans would want to have access to him as a Jinchuuriki alone, the power of that clan would automatically grow in the village, we suspect several have at least guessed at his parentage."

"What this boils down to Iruka," the Hokage stated interrupting his student, "is that the clans outmaneuvered each other until I was worried putting Naruto with any clan might lead to violence and a civilian family is out since most of them are either afraid of Naruto or of the reprisal that would occur if they were to adopt him."

"And your worried something similar would occur with a tutor?"

"Yes if we were to arrange for a tutor from the chūnin or jōnin ranks, most are connected to a clan and as for those from the civilian ranks the clans would probably just accuse me of trying to influence the boy toward my own clan since any ninja chosen would likely support myself politically. "

Iruka felt his anger build, there had to be someway to help Naruto!

"What about a genin?" he asked.

"A genin?"

"Well genin are usually considered neutral in Village politics. No one could accuse you of having a genin trying to sway Naruto, especially if the genin was a civilian. A good talented genin could help build up his fundamentals and you could make it a mission. I have hired genin to help with class activities before as part of D-ranks so there would even be a precedent for it."

Jiraiya started to say something but paused thing about Iruka's suggestion. He turned to the Hokage. "You know Sensei, that could work, in fact I have idea for the perfect genin."

"You don't mean?"

"Why not? He might refuse to lead a team but he has never refused a mission right? Can you think of anyone better to train Naruto in fundamental genin skills?"

Iruka looked back and forth between the Hokage and the Sannin. He had no idea what exactly they were planning but he felt a sense of relief that Naruto might finally get the help he deserved.

 **1**

"Naruto! Get back here!" an annoyed chūnin shouted.

"Nope." he replied mostly to himself.

The orange wearing ninja in training had just pulled of a prank that involved chili, dove feathers, and three stolen screws from the chair of chūnin in charge of orphan affairs. The jerk had tried to decrease the stipend Naruto was allotted as a orphan living on his own, the Hokage had put an immediate stop to that, but Naruto thought a little revenge of his own was in order. Naruto was so pleased with himself he failed to notice the path in front of him and found his chase brought to an abrupt end when he slammed headfirst into his Sensei's awaiting fist.

"Oww! Iruka-sensei! What was that for?" Naruto complained furiously rubbing his head glaring at his teacher.

"What do you think it was for? What trouble have you gotten yourself into now Naruto?"

Naruto grinned up at him. "Nothing really bad Sensei, just showing some overweight chūnin they can't pick on me."

Iruka rubbed his forehead in a vain attempt to stop the headache he felt coming, as he did the chūnin who had been in pursuit of Naruto finally caught up.

"I'll be taking that brat with me!" he said grabbing Naruto's arm and dragging him to his feet. Iruka frowned at the treatment.

"Now I know Naruto may be causing some trouble but don't you think you're being a bit aggressive?" asked Iruka.

"A demon brat like him only understands when you show him whose boss," he said shaking Naruto for good measure, "and if he think I'm bad he won't like what my squad leader has in store for him."

"Well he's going to have to wait his turn." Iruka commented.

"Why, you going to do something about it?"

"Me? No. But the Hokage is looking for him. Sent me to get him in fact, and you know how cranky he can be with delays, but if your squad leader thinks it's worth it go ahead, I'll just head back and inform him."

The chūnin got a bit pale. "Er...well we wouldn't want to be the Hokage waiting and I'm sure whatever he has in store will be more than appropriate."

"So can I take him then?"

The chūnin released Naruto's arm reluctantly. "Fine he's all yours but if he escapes again you have to deal with the Hokage!" he shouted before he raced off.

Naruto looked up at Iruka and started to laugh. "That was great Sensei! He really bought it! The look on his face when you mention the Old Man was priceless!"

Iruka's expression when stern and he leaned over until he was almost eye to eye with his student.

"It's not a joke Naruto. The Hokage wants to see you immediately."

Now Naruto's face went pale. "Jiji. Why? This is the first prank I've done in days! He couldn't possibly know about it yet!"

"He sees all Naruto. You should know that by now." Iruka said his face a slab of granite eying Naruto as if he were a bug about to be squashed, suddenly the effect was ruined as a chuckle escaped his lips. The small crack escaped to his entire face and he couldn't help laughing at his worried student.

"Not funny Iruka-sensei! You could have given me a heart attack!"

"Serves you right for playing pranks when you should be training. The Hokage does want to see you Naruto but it has nothing to do with your prank. You lucked out this time."

"Then what does Jiji want to see me about?"

"He'll explain everything when we get there. Now come along, unless you do want see what he's like after a unnecessary delay I suggest you hurry up." Iruka said as he headed toward the Hokage tower.

Naruto quickly followed.

 **2**

Iruka ushered his favorite, but most troublesome student, into the Hokage's office, the young teacher noticed Jiraiya was no where to be seen. Naruto was looking apprehensively around the room, still thinking he might be in trouble, and ready to try to a make a dash for it if the situation required. When he saw the typical friendly smile on his jiji's face he visibly relaxed and approached the Hokage with a familiarity many in the village would envy.

"Hey Jiji I heard you wanted to see me?"

"Indeed Naruto, I was going to ask how you managed to use dove feathers with such creativity?" he said amiably.

Naruto spun around with a accusing eye at his teacher. "You said he didn't know yet!"

Iruka held up his hands in a gesture of defense. "I wasn't sent about it Naruto, I promise!"

"Iruka is telling the truth Naruto, I have other sources to enlighten me to your pranks and, no matter well deserved, I would prefer you limit yourself to targets I have not already chastised."

"He shouldn't be pranking anyone Lord Hokage, he should be focused on his studies."

The Hokage took a drag from his pipe before he answered. "You are right of course,Iruka but a few pranks every so often can be good the soul." he said with a twinkle in his eye.

Naruto beamed up at Iruka. "See Iruka-sensei Jiji likes my pranks."

A small bit of killing intent filled the air. "Be that as it may Naruto, for one who spends so much time thinking up clever schemes I would think you would be doing far better in your Academy studies that you have been."

Naruto squirmed under the Hokage's gaze and rubbed the back of his neck sheepishly. "I know Jiji and I have been trying hard, I really have, but it seems no matter how hard I try I keep messing things up!"

The Hokage sighed and the killing intent faded from the air. "I know my boy and it's not entirely your fault, that's part of the reason I've brought you here today, I think it's high time we do something about that."

"What do you mean Jiji?"

"Your Sensei has been keeping me informed of your development in classes and it is his opinion you would benefit from a private tutor to help improve your ninja skills and after hearing his reasons I agree with him."

Naruto perked up at this, he knew most of the teachers didn't like him, and while a teacher almost never outright sabotaged him, he couldn't count the number of times a question of his was ignored or a explanation given that Naruto was sure was meant to just leave him confused. Iruka was his only teacher who tried to give him one on one time that he knew he needed. A tutor could make up for a lot if they were actually going to teach him.

His excitement bubbled through. "Really Jiji! That's awesome! I thought only clan kids could get that kind of help!"

The Hokage breathed out another bit of smoke. "True Naruto, most tutor are only available for clan children or civilian children with wealthy parents, but most of those tutor are elite trainers, that is more than you need at this time. What me and your Sensei have in mind is more simple. We will hire an unattached genin to drill you the basics until you get them down, I am well within my rights to provide this to you out of the Orphan funds set aside by the council."

Naruto chuckled. "Well I would rather have a super strong elite jōnin but I will take what I can get Jiji! Give me a few weeks and I'll be stronger than he is. Believe it!"

Sarutobi smiled at boy. "Well, we'll see how you well you do in time, but there are a few caveats Naruto that you must accept before I will confirm this."

"Caveats Jiji?"

"Rules you must follow."

"Okay like what Jiji?"

"First. No pranking while your in training. I know it's one of your favorite hobbies but I will not be able to justify paying the additional funds if I have to then defend your little jokes understood?"

Naruto sighed, "Understood Jiji." The Hokage mentally sighed in relief. While in truth he did enjoy Naruto's pranks, it would be a welcome break to not have to listen to the civilian council for awhile and some time out of the public eye might be good for Naruto.

"Second. While your training with your Sensei you will obey him like you would myself or Iruka-sensei." Which wasn't all that well, Hiruzen thought to himself. "You will be still be attending the Academy but your new teacher does have permission to take you out of class as needed. He will be working with Iruka to make sure you have time for your studies while your ninja skills develop."

"And finally Naruto I have one more rule. Assuming this works well and your skills improve you are still not to take another early graduation test."

"What! Come on Jiji that's not fair!" If I can't take the test how can I become Hokage?" said Naruto with a bit of hurt in his voice.

"A tree that lasts is built on a firm foundation Naruto." said the Hokage. You need to make sure your basic skills are mastered before we send you out into the world as a ninja Naruto. I don't want to just get good enough to pass a test, if you want to have my hat one day I want you have the abilities to get here one day."

Naruto thought it over in his head. As things stood now he was in danger of eventually failing out the Academy if things didn't change. If the Hokage felt this was the best path for him he would trust it.

"I understand Jiji." he said nodding with conviction. "And I agree to all your cave...ates...er..rules."

"Very good Naruto. And don't lose heart my boy. If your Sensei's think it's time for you to take the test early I may reconsider."

Naruto held in his excitement but made a silent vow to show Jiji he would be good enough to graduate early some day.

"So when do I meet my new teacher Jiji?"

"Right now." the Hokage said and with a small gesture to a unseen Anbu one of the hidden doors in the Hokage office opened and Naruto looked but all he could see was shadows, what he heard however was a different matter.

He heard the soft sounds of snoring. Then sounds of a frustrated Anbu trying to wake someone could be heard followed by a snort as said someone abruptly woke.

"What?...oh, finally time to meet the brat. Hiruzen always had to make things to dramatic." Some more whispers. "Keep your mask on sonny I'm moving!" the voice said annoyed. The Hokage rubbed his temples.

Out of the shadows came a old man who, despite sounding ill-tempered at being woken up from a well deserved nap, had a pleasant enough look on his face. He walked in with a slight limp and had a large assortment of odds and ends on his uniform that had looked as if they had been there for years. Naruto stared at the genin in shock and said the first thing that came to his mind.

"Your ancient!" he exclaimed. Naruto was not fast enough to avoid the fist that slammed on top of his head.

"Who are you calling ancient you little chibi!" he said back angrily. He turned to the Hokage. "I thought you said you wanted me to help someone in the Academy? This little runt has to still be in pre-school!"

The Hokage shook his head. "This is Naruto Uzumaki, he is in the Academy I assure you Kosuke. He will be your student for the foreseeable future." The Hokage turned his attention back to his adopted grandson who was still rubbing his head. "Naruto this is Kosuke Maruboshi, he will be the genin assisting in your training."

"No way! This guy's a genin! He's way to old! How am I supposed to learn anything from him?"

"I know more than you do brat! Why do I need to take on a student anyway?"

"Naruto, I assure you Maruboshi- _sensei,_ " Hiruzen said stressing the word, "is more than qualified to teach you everything you must learn to become a ninja. Kosuke, while you may not want to run a team you have gathered an incredible amount of knowledge over the years and if you were to fall in combat that would be lost, it's past time you take on students and begin to pass on what you have learned. You both will work together on this." he said addressing the ninja. They both took note of the finality in the order.

"Hai Hokage-sama" replied Kosuke.

"If you say so Jiji." said Naruto.

"When do I start?" asked the genin.

"The day is still young, why don't you start now?"

"As you wish, come on chibi."

"I am not a chibi!" he said to the retreating ninja. He turned to Sarutobi. "You sure about this Jiji?" he asked.

The Hokage smiled. "Give it time Naruto, I'm sure you'll find Maruboshi has a lot to each you." Naruto shrugged in acceptance and left the office following his new sensei.

Iruka, who had been silent through the conversation, could not hold it in anymore. "You got the Eternal Genin to tutor Naruto?" he said incredulously.

"Only a slight modification to your suggestion Iruka."

"I would say Lord Hokage, he is certainly skilled enough, but he has never been a teacher before, do you think he can handle Naruto?"

"Did you know Kosuke was an apprentice of my Sensei?"

"The Second Hokage! I had no idea."

"The knowledge is mostly lost or forgotten, but Kosuke had has a hand in teaching dozens of ninja over the years just from the benefit of being on the same squad as him. Many discount him for being a genin, the wiser shinobi know his strength is closer to a jōnin, but most don't realize the sheer knowledge he has locked away in that head of his over the years, and since most civilians would discount Kosuke as a failed shinobi there will be no grounds for favoritism. Many will actually think it's a token gesture or compromise on my part, not knowing Naruto is getting some of the best training a student could receive."

 **3**

Naruto followed Kosuke Maruboshi as best he could, despite appearances the old man was fast, until they came to one of the many training grounds surrounding Konoha, this one being training ground 15, which was well forested and had a decent size lake fed by a few small streams. Kosuke stopped them by the lake and waited for Naruto to catch his breath, which only seemed to take moment.

 _Well I'll say this for the chibi, he has good stamina for his age_ Kosuke though, he had gradually increased his speed and Naruto had no real difficulty keeping up. Kosuke sat down cross-legged on the forest floor and gestured for the boy to do the same.

"Alright chibi, I may not want to teach anyone, but if the Hokage commands it I won't argue, so why don't you tell me what you need help in?"

Naruto blinked, that was straightforward, and he was not used to someone just asking him what he needed. Either teachers ignored him or Iruka and Jiji usually encouraged him to think of his own solutions.

"Well I'm decent at my Transformation and Substitution Jutsu but my Clone Jutsu sucks."

"And?"

"Um...I don't know, I mean I'm dead last in class so I need help in a lot a guess."

"Dead last? Who cares about some stupid Academy ranking? That crap doesn't mean anything once you graduate."

"Yeah, well you aren't the one pounded into the ground in spars." Naruto grumbled.

"Heh, I'll have you know I've been smashed into the ground by the best of them kid." he rapped on one of his legs and from the sound Naruto knew it was wooden. He looked at the genin, question on his lips.

"No chibi, I won't tell you, but take my word for it, losing in the Academy is better than losing on the field, it gives you a chance to learn from your mistakes and learn to take a hit. Whose the best student in your class?"

"Sasuke-teme." he growled

The old man laughed. "He's your rival I take it? Well someday he'll get in the field and he will not be prepared when he faces the first real enemy stronger than himself, but you are already used to facing that, so whose better prepared for ninja life?"

"But I've never even come close to beating him!"

"That's why we're here right?" The old man stood and looked down at Naruto. "Let's see how strong you really are then." He gestured at the boy.

"Attack me."

 **Author's Note: I always thought Kosuke was a underutilized character. This was a guy around through 3 of the 4 hokage's terms and was personally trained by two of them. I thought he would make a great character for the whole "Naruto actually gets proper training when he's young" story so we'll see how it goes.**


End file.
